way, specifying @code{tabulated-list-mode} as the second argument
(@pxref{Derived Modes}). The body of the @code{define-derived-mode}
form should specify the format of the tabulated data, by assigning
-values to the variables documented below; then, it should call the
-function @code{tabulated-list-init-header} to initialize the header
-line.
+values to the variables documented below; optionally, it can then call
+the function @code{tabulated-list-init-header}, which will populate a
+header with the names of the columns.
The derived mode should also define a @dfn{listing command}. This,
not the mode command, is what the user calls (e.g., @kbd{M-x
@code{tabulated-list-format}).
@end defun
-@defun tabulated-list-print &optional remember-pos
+@defun tabulated-list-print &optional remember-pos update
This function populates the current buffer with entries. It should be
called by the listing command. It erases the buffer, sorts the entries
specified by @code{tabulated-list-entries} according to
If the optional argument @var{remember-pos} is non-@code{nil}, this
function looks for the @var{id} element on the current line, if any, and
tries to move to that entry after all the entries are (re)inserted.
+
+If the optional argument @var{update} is non-@code{nil}, this function
+will only erase or add entries that have changed since the last print.
+This is several times faster if most entries haven't changed since the
+last time this function was called. The only difference in outcome is
+that tags placed via @code{tabulated-list-put-tag} will not be removed
+from entries that haven't changed (normally all tags are removed).
@end defun
@node Generic Modes